CN111771637B

CN111771637B - Method for screening nitrogen-efficient germplasm of rape and breeding nitrogen-efficient variety of rape

Info

Publication number: CN111771637B
Application number: CN202010778360.XA
Authority: CN
Inventors: 邹小云; 熊信果; 黄杨; 潘皓
Original assignee: INSTITUTE OF CROPS JIANGXI ACADEMY OF AGRICULTURAL SCIENCES
Current assignee: INSTITUTE OF CROPS JIANGXI ACADEMY OF AGRICULTURAL SCIENCES
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2022-08-23
Anticipated expiration: 2040-08-05
Also published as: CN111771637A

Abstract

The invention belongs to the technical field of crop breeding, and particularly relates to a method for screening nitrogen-efficient germplasm of rape and breeding a nitrogen-efficient variety of rape. The breeding method of the nitrogen-enriched high-efficiency rape variety comprises the steps of field planting, germplasm preselection, germplasm determination, hybridization improvement and the like, the invention firstly provides the breeding method of the nitrogen-enriched high-efficiency rape variety based on phenotypic characters of rape root stem thickness, overground part dry matter weight and the like, and compared with the traditional breeding method of the nitrogen-enriched high-efficiency rape variety, on one hand, the complex procedures of labor waste and financial waste for nitrogen content determination are reduced; on the other hand, the method has the advantages of quantification, mechanical repetition, non-transgenic technology, no risk, high selection efficiency, easy implementation, low cost and the like.

Description

Method for screening nitrogen-efficient germplasm of rape and breeding nitrogen-efficient variety of rape

Technical Field

The invention belongs to the technical field of crop breeding, and particularly relates to a method for screening nitrogen-efficient germplasm of rape and breeding a nitrogen-efficient variety of rape.

Background

Rape is an important oil crop in China, and the rape cultivated in China mainly comprises cabbage type rape, Chinese cabbage type rape and mustard type rape. A large amount of edible vegetable oil is consumed in China every year, and the rape becomes the most important oil crop for ensuring the supply safety of the edible vegetable oil in China. The rape has large fertilizer demand, and more fertilizer is put into production, but the fertilizer utilization rate is lower, thereby not only causing resource waste, but also bringing potential risks of agricultural non-point source pollution. At present, the improvement of the fertilizer utilization efficiency of rape, particularly the utilization rate of nitrogen fertilizer, becomes a research hotspot in the field of plant nutrition.

The application of the nitrogen fertilizer plays a great role in improving the yield of the rape per unit area. However, the application rate of nitrogen fertilizers tends to increase with the increase of the yield per unit area. The excessive application of nitrogen fertilizers brings a series of problems to the production of the rape: firstly, the sugar content in the plant body is relatively insufficient, the mechanical tissue in the stem is not developed, lodging is easily caused, pest damage and later-stage greedy are caused, the yield is reduced, and the phenomenon of secondary flowering of the rape can also be caused by excessive application of nitrogen fertilizer in the later stage. And secondly, the quality is reduced, the fertilization level is improved, and although the protein content of grains is improved, the oil content and the oil yield are reduced. Thirdly, the production efficiency of the unit nitrogen is low, the cost is increased, and the benefit of rape cultivation is reduced. Fourthly, a series of environmental and ecological problems such as water eutrophication, increased nitrate salt content of underground water, soil, atmosphere and underground water pollution are caused. Under the same condition, compared with germplasm with low utilization rate of nitrogen fertilizer, nitrogen-efficient germplasm can apply less nitrogen fertilizer to obtain higher yield, and meanwhile, the risk of environmental pollution caused by nitrogen fertilizer which is not utilized in soil can be reduced by reducing the application amount of the nitrogen fertilizer, and the planting cost can be saved. Therefore, the screening of the nitrogen-enriched rape germplasm and the breeding of the nitrogen-enriched rape variety are important measures for further improving the rape planting area and ensuring the safety of the edible vegetable oil, and are also important ways for promoting the efficient utilization of resources, improving the economic benefit of production and realizing the sustainable development of rape.

Currently, in the breeding of nitrogen-enriched rape germplasm, the nitrogen content of rape is generally sampled and determined at the seedling stage or the mature stage of the rape, the nitrogen absorption and utilization efficiency is calculated, then the nitrogen absorption and utilization efficiency is compared, the rape variety with high nitrogen absorption and utilization efficiency is hybridized and bred with the existing high-quality high-yield rape variety, but due to the fact that the nitrogen efficiency is determined, the complex procedure is added to the breeding work, the difficulty is increased in the variety improvement work, and the improvement of the breeding efficiency of the nitrogen-enriched rape variety is hindered.

Disclosure of Invention

Therefore, the invention aims to overcome the defects of complex process, low efficiency and the like of the breeding of the nitrogen-efficient rape germplasm in the prior art, thereby providing a method for screening the nitrogen-efficient rape germplasm and a method for breeding a new nitrogen-efficient rape variety.

Therefore, the invention provides the following technical scheme:

the invention provides a method for screening nitrogen-efficient germplasm of rape, which comprises the following steps:

planting in the field: concentrating the rape germplasm with basically consistent growth period, known nitrogen efficient germplasm and known high-yield germplasm in a low nitrogen level in a field for planting, and respectively measuring the root thickness and the dry matter weight of the overground part of all rape germplasm materials in a seedling stage, a bolting stage and a maturation stage;

germplasm preselection: carrying out variance analysis and significance test on the measurement data obtained in the steps, and screening out rape germplasm which has the dry matter weight of the thick rootstock and the overground part which is more than 10% higher than the average value of all tested rape germplasm in the same measurement period and has significant difference with the known nitrogen efficient germplasm and the known high-yield germplasm;

germplasm determination: under the normal nitrogen applying level of the rape, the rape germplasm screened in the germplasm preselection step and the known high-yield germplasm are intensively planted, and the rape germplasm with thick rootstock, heavy overground part dry matter, more than 5% higher single-plant effective pod number and single-plant seed yield than the known high-yield germplasm, which reaches the standard in quality and character and is lodging-resistant is screened out in the maturation period, namely the high-efficiency nitrogen applying germplasm of the rape.

Further, the known nitrogen-efficient germplasm is one of Xiangyou 15, Brassica napus No. 13, H6;

the known high-yield germplasm is one of the No. 11 Gangshu, No. 8 Gangyou hybrid and No. 19 Gangyou hybrid.

Further, the nitrogen application amount of the low nitrogen level in the field planting step is lower than the nitrogen application amount of the normal nitrogen application level in the germplasm determination step by more than 8 kg/mu.

Further, the nitrogen application amount in the field planting step is 2-4 kg/mu;

the nitrogen application amount in the germplasm determining step is the nitrogen application amount recommended by the local conventional planting field, and the recommended dosage in Jiangxi is 11-13 kg/mu.

Further, the screening standards of the quality traits are that the oil content is higher than 42%, the content of glucosinolate is lower than 40 mu mol/g and the content of erucic acid is lower than 1%.

Further, the alternative rape germplasm is cabbage type rape germplasm, Chinese cabbage type rape germplasm or mustard type rape germplasm.

The invention also provides a breeding method of the nitrogen-efficient rape variety, which comprises the following steps:

and (3) performing hybridization improvement on the rape nitrogen high-efficiency germplasm screened out by the screening method, performing microspore culture or continuous selfing on the hybridization improved progeny, and screening to obtain the rape nitrogen high-efficiency variety.

Further, the microspore culturing step comprises: and (3) carrying out microspore culture on the improved filial generation to obtain doubled microspore seedlings, planting the doubled microspore seedlings in the field, harvesting DH line seeds, planting the DH line seeds in the field, examining indexes such as root and stem thickness, overground part dry matter weight, single plant effective silique number, single plant seed yield, lodging resistance, oil content, thioglucoside content, erucic acid content and the like during growth, and screening out the nitrogen-efficient rape variety.

Furthermore, the generation number of the continuous selfing is 7-9, the indexes of the thick rootstock, the heavy dry matter of the overground part, the effective pod number of a single plant, the yield of single plant grains, lodging resistance, oil content, thioglucoside content and erucic acid content are considered during the growth period, and the nitrogen-efficient variety of the rape is screened out.

Furthermore, the screening standard is that the screening of the root and stem thickness, the dry matter weight of the overground part, the effective pod number of a single plant and the yield of single plant seeds in the mature period are all higher than the known high-yield germplasm by more than 5 percent; the oil content is higher than 42%, the glucosinolate content is lower than 40 mu mol/g, and the erucic acid content is lower than 1%.

Further, the water and fertilizer management of the field planting and the centralized planting is conventional operation, and the difference lies in the control of nitrogen application amount. The overall fertilization principle is as follows: and (3) heavily applying a base fertilizer, additionally applying a phosphorus-potassium fertilizer and applying a boron fertilizer.

Further, in the field planting step, 2-4kg of nitrogen fertilizer is applied to each mu of field in terms of pure N; with P ₂ O ₅ 5-7kg of phosphate fertilizer is applied to each mu of field; with K ₂ O, metering, and applying 5-7kg of potash fertilizer per mu of land; applying 1.5-1.6kg of borax to each mu of field. In the centralized planting step, 11-13kg of nitrogen fertilizer is applied to each mu of land; with P ₂ O ₅ 5-7kg of phosphate fertilizer is applied to each mu of field; with K ₂ O, metering, and applying 5-7kg of potassium fertilizer to each mu of field; applying 1.5-1.6kg of borax to each mu of field.

Furthermore, in each mu of field, 60 wt% of nitrogen fertilizer in the nitrogen fertilizer is used as base fertilizer, 20 wt% of nitrogen fertilizer is used as seedling fertilizer, and 20 wt% of nitrogen fertilizer is used as bolting fertilizer;

the phosphate fertilizer is completely used as a base fertilizer;

70 wt% of potassium fertilizer in the potassium fertilizer is used as base fertilizer, and 30 wt% of potassium fertilizer is used as bolting fertilizer;

90 wt% of borax in the borax is used as base fertilizer, 10 wt% of borax is used as bolting fertilizer, and the borax is sprayed on leaf surfaces.

Furthermore, when the plants are planted in the field and in a centralized way, the plant spacing is 10cm, and the row spacing is 33 cm.

In the present invention,

root and stem thickness: refers to the diameter of the base of the cotyledonary node of the plant stalk, and is generally measured with a vernier caliper.

Rape nitrogen high-efficiency germplasm (variety): the rape seed quality (variety) has higher nitrogen absorption efficiency under low nitrogen and higher nitrogen fertilizer utilization efficiency and higher rape seed yield under the condition of proper nitrogen fertilizer dosage.

The technical scheme of the invention has the following advantages:

1. the invention provides a method for screening nitrogen-efficient germplasm of rape, which comprises the steps of field planting, germplasm preselection, germplasm determination and the like, and provides a method for screening the nitrogen-efficient germplasm of rape based on phenotypic characters of rape root stem thickness, overground part dry matter weight and the like for the first time, compared with the traditional method for screening the nitrogen-efficient rape germplasm, on one hand, the complex procedures of labor and cost for measuring the nitrogen content are reduced; on the other hand, the method has the advantages of quantification, mechanical repetition, high selection efficiency, easy implementation, low cost and the like.

According to the screening method of the high-efficiency rape nitrogen germplasm, the nitrogen application amount in the germplasm determining step is recommended to be used in a local conventional planting field. The arrangement has the effect of being actually combined with local production and application.

2. The breeding method of the nitrogen-rich high-efficiency rape variety comprises the steps of field planting, germplasm preselection, germplasm determination, hybridization improvement and the like, firstly provides the breeding method of the nitrogen-rich high-efficiency rape variety based on phenotypic characters such as rape root stem thickness and overground dry matter weight, and reduces the complex procedures of labor and cost for measuring the nitrogen content compared with the traditional breeding method of the nitrogen-rich high-efficiency rape variety on one hand; on the other hand, the method has the advantages of quantification, mechanical repetition, non-transgenic technology, no risk, high selection efficiency, easy implementation, low cost and the like.

The rape variety bred by the breeding method of the nitrogen-enriched high-efficiency rape variety provided by the invention has stable character and strong repeatability, and compared with Xiangyou No. 15, the nitrogen absorption and utilization efficiency is 46.36%, which is improved by 7.27%; the yield of the rape seeds is 146.32 kg/mu, which is improved by 8.22 percent.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flow chart of the method for breeding the nitrogen-rich variety of rape provided by the invention.

Detailed Description

The following examples are provided to further understand the present invention, not to limit the scope of the present invention, but to provide the best mode, not to limit the content and the protection scope of the present invention, and any product similar or similar to the present invention, which is obtained by combining the present invention with other prior art features, falls within the protection scope of the present invention.

The examples do not show the specific experimental steps or conditions, and can be performed according to the conventional experimental steps described in the literature in the field. The reagents or instruments used are conventional reagent products which are commercially available, and manufacturers are not indicated.

Example 1

The embodiment provides a method for screening nitrogen-efficient germplasm of rape and breeding a nitrogen-efficient variety of rape, which comprises the following steps of:

planting in the field: 96 shares of brassica napus germplasm (including a nitrogen high-efficiency variety Xiangyou No. 15 and a high-yield variety Zhongshuan No. 11, which are shown in Table 1) with basically consistent growth periods are selected, and all germplasm is sown in a paddy field with good drainage in local places (Nanchang city in Jiangxi province) in 10 th month in 2012 (the paddy field is a medium paddy field planted with half of nitrogen fertilizer once). Applying 3kg of pure nitrogen and phosphorus (P) to each mu of the soil ₂ O ₅ )6kg, potassium (K) ₂ O)6kg and borax 1.5 kg. Wherein, nitrogen fertilizer is applied at 60% base, and seedling fertilizer and bolting fertilizer are respectively applied at 20%; completely applying the phosphate fertilizer at the bottom; 70% of potassium fertilizer is applied on the bottom, and 30% of potassium fertilizer is used as a bolting fertilizer; 1.35kg of borax is applied at the bottom, and 150g of borax is sprayed on leaf surfaces in the bolting period. Fertilizing, turning over, ditching and making a compartment of the test field at one time by using a rape seeder (without adding seeds), then sowing transverse ditches, sowing 6-8 rows of each germplasm, sowing the seeds at a row spacing of 33cm and sowing the seeds at a plant spacing of 10cm, and repeating for 3 times.

TABLE 1 test Brassica napus germplasm

Germplasm preselection: in 12 months in 2012, each repeated germplasm is respectively selected as a sample from 6 typical plants in the seedling stage, taken back to a laboratory for measuring the root and stem thickness, immediately placed into an oven for drying at 105 ℃ for 30 minutes, cooled to 75 ℃, dried and weighed, and screened out the rape seeds with the root and overground dry matter weight more than 10% higher than the average value of all alternative rape seeds in the same measuring period and with obvious differences from 15 # Shaanxiang oil and 11 # Zhongshuang oil, including Monty, 8 # Shaanxiang oil, Surpass 440, 15 # golden oil, 023 yellow oil and 16 # Ningyou, and the specific results are shown in Table 2. In the middle ten days of 2 months in 2013, 6 typical plants are selected from each repeated germplasm in the bolting period respectively as samples, the samples are taken back to a laboratory for measuring the root and stem thickness, the samples are immediately put into an oven for drying at 105 ℃ for 30 minutes, the temperature is reduced to 75 ℃, the samples are dried and weighed, the dry matter weight of the root and the overground part is selected to be more than 10 percent higher than the average value of all the alternative rape germplasms in the same measuring period, and the screened samples have significant differences with the control No. 15 Hunan oil and No. 11 rape germplasms in the middle-double 11, including No. 15 gold oil, Monty, No. 8 Shaanxi oil, Surpass 440, yellow 023 and Ningyou 16, and specific results are shown in Table 3. In early 5 months in 2013, 6 typical plants are selected from each repeated germplasm in the maturation period as samples, the samples are hung with labels, the samples are placed in a hanging room for ventilation and air drying, the root and stem thicknesses are measured in the middle ten days of 6 months, the samples are bagged, placed in an oven for drying at 75 ℃ and then weighed, the dry matters on the root and the overground part of the selected rape seeds are more than 10 percent higher than the average value of all the alternative rape seeds in the same measurement period, and the screened rape seeds have significant differences with the control Xiangyou No. 15 and Zhongshuang No. 11, including Monty, Shanyou No. 8 selection, Surpass 440, Jinyou 15 and Huang023, and the specific results are shown in Table 4. The dry matter weight of the thick roots and the thick overground parts of the stems in the seedling stage, the bolting stage and the maturation stage is more than 10 percent higher than the average value of the same determination period of all the alternative rape germplasms, and the selective identification of the rape germplasms Monty, No. 8 selection of Shaanxi oil, Surpass 440, gold oil 15 and yellow 023 which have significant difference with the control No. 15 Hunan oil and No. 11 Zhongshuang oil is centrally planted.

TABLE 2 investigation results of seedling stage

Note: the different lower case letters in the same column indicate differences up to a 5% significance level.

TABLE 3 Young shoot period investigation results

Note: the different lower case letters in the same column indicate a difference of up to a 5% significance level.

TABLE 4 maturity survey results

Germplasm determination: and (5) sowing the preselected germplasm Monty, No. 8 Shaanxi, Surpass 440, gold oil 15, yellow 023 and No. 11 of the control varieties in the paddy field with good local drainage in 10 months in 2013. Applying 12kg of pure nitrogen and phosphorus (P) per mu ₂ O ₅ )6kg of potassium (K) ₂ O)6kg and borax 1.5 kg. Wherein, nitrogen fertilizer is applied at 60% base, and seedling fertilizer and bolting fertilizer are respectively applied at 20%; completely applying the phosphate fertilizer at the bottom; 70% of potassium fertilizer is applied as base fertilizer, and 30% of potassium fertilizer is used as bolting fertilizer; borax 1.35kg is applied on the bottom, and 150g is sprayed on the leaf surface in the bolting stage. The rape seeder (without seeds) is used for completing fertilization, plowing, ditching and compartment making of the test field at one time, then transverse ditch sowing is carried out, each seed quality is sowed with 10 rows, the row spacing is 33cm, the plant spacing is 10cm, and the operation is repeated for 3 times. Selecting 10 typical plants as samples from each germplasm in the mature period of 5 months in 2014, hanging labels, placing in a hanging room for ventilation and air drying, and then examining the root thickness, the overground dry matter weight and the effective horn fruit of each plant in 6 middle-month ten daysThe specific results of the traits such as number and single plant seed yield are shown in Table 5. And screening the rape germplasm of Monty and Shaanxi No. 8 with two thick roots and stems, heavy dry matter on the overground part, more than 5% higher effective pod number of a single plant and yield of single plant grains than that of the double No. 11 in the contrast, namely the nitrogen high-efficiency germplasm.

TABLE 5 germplasm determination survey results

And (3) hybridization improvement: in 5 months in 2014, pre-selected germplasm Monty, No. 8 Shaanoil selection, Surpass 440, gold oil 15 and yellow 023 are planted in a test field in Xining City of Qinghai province in other places according to a conventional cultivation technology, 2 rows are sown in each variety, 10 seedlings are fixed in each row, a determined nitrogen efficient variety Monty and No. 8 Shaanoil selection are selected to carry out positive and negative crossing when blooming in 7 months in 2014, and Monty multiplied by No. 8 Shaanoil selection and No. 8 Shaanoil multiplied by Monty two hybridization combinations are configured. In 10 months in 2014, F1 generation seeds obtained by hybridization combination of Monty multiplied by Shaanoil No. 8 and Shaanoil No. 8 multiplied by Monty are planted in 6 rows in south Chang in Jiangxi according to the method of germplasm determination steps, and excellent single plants are selected for microspore culture in 2 months in 2015. Then, the multiplied microspore seedlings are planted in the field, 53 parts of DH seeds of Monty multiplied by Shaanxi oil No. 8 (Z1) and 34 parts of doubled Shaanxi oil No. 8 multiplied by Monty (Z2) DH seeds are harvested in a bagging mode, each part of obtained DH seeds are directly planted in south Chang in Jiangxi for 10 months in 2016 according to a method of a germplasm determination step, the yield and the stress resistance are inspected during the growth period, two quality indexes of oil content, glucosinolate content, erucic acid content and the like are analyzed, DH lines with the glucosinolate content lower than 40 mu mol/g and the erucic acid content lower than 1 percent and the oil content lower than 42 percent are removed, and finally, Z1-27 and Z2-19 DH lines are preferably selected, the nitrogen high-efficiency rape varieties are determined, and can be directly applied to nitrogen high-efficiency breeding;

simultaneously, respectively harvesting two combined F2 generation seeds in 6 months in 2015, directly mixing the two combined F2 generation seeds in 10 months in 2015 according to a method for determining germplasm steps, sowing in Nanchang city in Jiangxi province, and respectively sowing each F2Combined planting area 150m ² And not less than 5000 plants are planted in each combination. And (2) inspecting the yield and the lodging resistance of single seeds, selecting preferably 225 single seeds from Monty multiplied by Shaanoil No. 8 and selecting preferably 213 single seeds from Shaanoil No. 8, intensively planting the two combined preferable single seeds for screening, continuously selfing, selecting the quality and comprehensive properties until F8 generations, analyzing two quality indexes of oil content, glucosinolate content and erucic acid content, and the like, removing strains with the glucosinolate content lower than 40 mu mol/g, the erucic acid content lower than 1% and the oil content lower than 42%, and finally preferably selecting 19XY196 (from Monty multiplied by Shaanoil No. 8) and 19XY384 (from Shaanoil No. 8 and multiplied by Monty), determining the strains as nitrogen high-efficiency varieties and directly applying to nitrogen high-efficiency variety breeding.

The nitrogen-enriched high-efficiency rape variety bred by the method is planted about 10 days in local 10 months according to the method of the germplasm determining step, rape seeds are harvested after the rape seeds are mature, the observed characters are stable, the repeatability is strong, and compared with Xiangyou No. 15, the nitrogen absorption and utilization efficiency is 46.36% averagely, and is improved by 7.27%; the average yield of the rape seeds is 146.32 kg/mu, and is improved by 8.22 percent.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. This need not be, nor should it be exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the spirit or scope of the invention.

Claims

1. A method for screening nitrogen-efficient germplasm of rape is characterized by comprising the following specific steps:

germplasm determination: under the normal nitrogen application level of the rape, carrying out centralized planting on the rape germplasm screened in the germplasm preselection step and the known high-yield germplasm, screening out the rape germplasm which has thick rootstock, heavy dry matter on the overground part, more than 5% higher effective pod number per plant and yield per plant seed than the known high-yield germplasm in the maturation period, has up-to-standard quality and characters and is lodging-resistant, namely the high-efficiency nitrogen germplasm of the rape;

the known nitrogen-efficient germplasm is one of Xiang oil 15, cabbage type rape No. 13 and H6;

the known high-yield germplasm is one of the No. 11 Gangshu, No. 8 Gangyou hybrid and No. 19 Gangyou hybrid;

the nitrogen application amount of the low nitrogen level in the field planting step is lower than the nitrogen application amount of the normal nitrogen application level in the germplasm determination step by more than 8 kg/mu;

the screening standards of the quality traits are that the oil content is higher than 42%, the content of thioglucoside is lower than 40 mu mol/g and the content of erucic acid is lower than 1%.

2. The method for screening nitrogen-efficient germplasm of rape as claimed in claim 1, wherein the rape germplasm is brassica napus germplasm, brassica napus germplasm or brassica juncea germplasm.

3. A method for breeding a nitrogen-rich high-efficiency rape variety is characterized by comprising the following steps:

and (2) performing hybridization improvement on the rape nitrogen-efficient germplasm screened by the screening method according to the claim 1 or 2, performing microspore culture or continuous selfing on a hybridization improved progeny, and screening to obtain the rape nitrogen-efficient variety.

4. The method for breeding the nitrogen-rich variety of rape as claimed in claim 3, wherein the step of microspore culture comprises: and (3) carrying out microspore culture on the improved filial generation to obtain a doubled microspore seedling, planting the doubled microspore seedling in the field, harvesting DH line seeds, planting the DH line seeds in the field, inspecting the root thickness, the dry matter weight of the overground part, the effective silique number of a single plant, the yield of the single plant, lodging resistance, oil content, the content of thioglucoside and the content of erucic acid in the growth period, and screening out the nitrogen-efficient rape variety.

5. The method for breeding the nitrogen-enriched rape variety as claimed in claim 3, wherein the generation number of the continuous selfing is 7-9, the indexes of the thick rootstock, the heavy dry matter of the overground part, the effective silique number of a single plant, the yield of a single plant grain, the lodging resistance and the oil content, the content of glucosinolates and the content of erucic acid are examined during the growth period, and the nitrogen-enriched rape variety is screened out.